Has anyone had any success with having the thrust surface re-welded? I haven't been able to find a shop that will do it yet. I have seen cranks online for anywhere from $700 to $3500. Not quite sure what to do. Any help would be appreciated. Thank you

augur wrote:Has anyone had any success with having the thrust surface re-welded? I haven't been able to find a shop that will do it yet. I have seen cranks online for anywhere from $700 to $3500. Not quite sure what to do. Any help would be appreciated. Thank you

Seen many cranks welded but never paid any attention to weather they welded the thrust bearing surface but if you do have it done make sure they know what they are doing I see so many welders use the wrong material for jobs. Out of curiosity can you post a picture of the bad area? Seems like you should be able to get a crank at a good price for that engine.

Thank you for the info. I can't post a pic because I already threw in a new thrust bearing and put everything back together. I have 26-30 thousandths end play and the thrust surface of the crank looks like used brake rotor.

Thanks guys, I appreciate the info both warning me not to run the engine and where to get my crank fixed. This is a great site. I couldn't get any of this info off a google search. This has been a very humbling project. Thanks again.

I wanted to share an update. I pulled my crank and got it down to Steve's custom Cranks in Pinellas Park. He re-welded the thrust surface and polished everything back up. $125 out the door. Thank you Steve!!!

augur wrote:I wanted to share an update. I pulled my crank and got it down to Steve's custom Cranks in Pinellas Park. He re-welded the thrust surface and polished everything back up. $125 out the door. Thank you Steve!!!

Thanks for the update. Many times there is not one, so there is no confirmation of an outcome, one way or the other.

Just seeing this prompted me to go back and look at your previous thread. Having re-read that, I want to give you a couple of words of caution. If this is stuff you know, don't be offended; I would rather run that risk than see you need to replay that crank game.

In reference to your first post, you said that "your prop pitch was limiting your engine rpms to 2200". I'm sure at the time, people (including myself) read past that and perceived it meant that was your chosen break-in rpm, which would be fine. However, you do not want to literally pitch the prop to hold the engine at those rpms. That 2k rpm should be as in real fast idle/half throttle rpms with minimal load, not wide open choked down with prop pitch. The primary intent at that point is to wear the lifters in to cam, not put excessive load on the crank. It should only require a minimum amount of pitch to accomplish that. Doing it in that fashion will also minimize excessive loading on the thrust bearing.

In your next post you mentioned that your prop is 13" at it's widest and about 8" at the tips, and questioned what max rpms that prop should turn. That sounds wide to me for a direct drive prop meant to turn 3k rpms. If you don't know what prop you have, you should confirm that, as it sounds like it may be for a belt drive. While 2800 -3000 rpms is typical for a direct drive, if it is not a direct drive prop you need to get one. A belt drive prop would almost certainly not play well with a new thrust bearing for very long. Also, they are not typically rated for as much rpm which could additionally be a safety issue. What manufacturer is it, and how long does it measure?

Again . . . I'm not trying to make an issue where there is not one,only meaning to try and help you avoid shooting yourself in the foot.

"The suppression of uncomfortable ideas may be common in religion and politics,but it is not the path to knowledge; it has no place in the endeavor of science." - Carl Sagan

Thanks for your input, I feel positive the pitch was too steep and it killed my thrust bearing. The motor runs great but just wouldn't rev past 2200 rpms with the prop. The boat is a 14ft cottonmouth and cruised 30mph at 1800rpms with 600lbs of passengers. That seemed like a great setup to me.

I need to take it to a PRO and get it set up right this time. Too much time and money at this point to make any more bad decisions.

Update- I pulled the crank and sent it to Steve's custom Crankshafts. He welded and polished it back up. The motor is re-assembled and running. The end play almost imperceptible with new mains and thrust bearings. I read some post on here that couldn't overstate how important the right lube is, so I filled it with 4qts Rotella 15-40, 1qt Lucas additive, and 4 oz comp cams 159 (that's a slimy mix!!) Ran it on trailer a few times enough to warm it up and check for fluid leaks, so far so good. So now what? I not quite sure how to proceed. I need to figure out where to set my timing, and pitch my prop, and most of all (not fry my thrust bearing and crank again).

My prop as near as I can tell is a 72 inch power production inc which seems to translate into a water walker signature series 8 inches at the tip and 12 inches at the widest. 6cyl aircraft or direct drive automotive.

Signature Series blades (which is what you want) measure a fat ten inches at the widest part.

The way you describe your current blades, I believe they are Powershift Plus blades, and as far as I know were the predecessors to the current WW Falcon blades. If that is the case, those were NOT meant to run on your Caddy.

Designed as wider, to turn less RPMs and would not be C/M thrust bearing friendly.

I have a set of Signatures here. Do I remember you being near Deland?

PM sent

"The suppression of uncomfortable ideas may be common in religion and politics,but it is not the path to knowledge; it has no place in the endeavor of science." - Carl Sagan